Traditional methods of printing on PET drinks packaging can create illegible or erasable printed codes that may also potentially damage the bottle. Beverage Packaging Innovation speaks to Sylvain Clement at Markem-Imaje about how the company's SmartLase technology and highly efficient product output ensure outstanding and reliable results.
Sylvain Clement: For the bottler as well as for the food producer, the main challenge is to make sure that every single product leaves the factory with a legible and permanent code. This code must be legible to the consumer because the objective is to make sure that, in case of any problem with the product, we will be able to get all the information about the batch, and then the producer will have the opportunity to analyse the problem and recall some products if necessary.
The code must not damage the bottle, the total cost of coding must be the lowest possible and the coding performance must be aligned with the high output rates of PET production lines, which is currently up to 81,000 bottles an hour for PET, and increasing. The Markem-Imaje 30W laser is able to code two-line/20-character codes at 100,000 bottles an hour at very high quality.
We have the highest code legibility in the industry (character shaping) and over 30% higher speed capability versus competitive 30W lasers thanks to our patented SmartLase Code Technology. This involves shaping characters using curves rather than traditional straight vectors. For example, an '8' is composed of four arcs rather than 29 segments. The code is therefore easier to read, and printing speed is greatly increased as there is less time lost to repositioning the laser for the next segment. The time saved means it can be used to code bolder characters for enhanced contrast and legibility.
SmartLase also affords us the highest code contrast in the industry thanks to the use of 9.3µ wavelength, which does not pierce PET but creates white bubbles on the package surface - a 'foaming effect' - with high contrast. This is vital for legibility on clear products like bottled water.
We measured a 60,000 MTBF (mean time between failures) for the full system, including the laser tube, the printhead and the controller, which is the highest in the industry. Our cooling system, with our SmartLase Code Technology, reduces the use of power and extends laser tube life, allowing an average of ten years of operation without the need for preventative part replacement. For more durability in harsh environments, SmartLase C laser bodies are made of stainless steel.
All SmartLase C lasers delivered and installed by Markem-Imaje are made with a guarding tunnel to make it a Class 1 laser device that can be used by anybody - a DVD player uses a Class 1 laser. The tunnel and its interlock are designed in such a way that an operator cannot pass their arm or hand in front of the laser beam without opening the tunnel, which switches the laser beam off instantly.
Laser technology is by definition 'green' as it doesn't emit any hazardous waste. Additionally, SmartLase C lasers from Markem-Imaje use up to $1,000 less in energy a year compared with other lasers in the beverage industry. Competitive lasers may also require plant air or additional cooling to reach the level of IP for protection against water spills, whereas our C lasers are natively IP55 without the use of plant air.
Last but not least, SmartLase C lasers are 80% recyclable, to comply with the WEEE directive.